During carcinogenesis, alterations occur in the biosynthesis of carbohydrate structures on the cell surface, and several different carbohydrates linked either to proteins or to lipids have been recognized to be tumor-associated antigens. Thomsen-Friedenreich (TF) disaccharide (Galβ1-3GalNAcα) is typically found O-linked to serine or threonine residues. TF-Ag (also known as T antigen) has been associated with several human carcinomas, including those found in the pancreas, colon, and breast, and on this basis has been referred to as a pan-carcinoma marker. TF-Ag is concealed from the immune system in normal adult tissues by extension with larger glycan chains. In cancer, the cellular glycosylation machinery may be disrupted leading to truncation of these chains and exposure of the TF antigen. New monoclonal antibodies and antibody fragments thereof which can target TF-Ag are desirable, and are provided by the present disclosure.